[ATM] John Dobson and a "glint of sunlight off of a raven's eye..."

["Jerry" <wa4guu@verizon.net>]

David Harbor mentioned the raven's eye.  I had just mentioned the same thing
in a private communication.

It is at least a little interesting. I would imagine that many on the have
no clue what Dave is talking about.

John Dobson wrote an article in Sky & Telescope about his telescope making.
I can't remember when but it was quite a few years ago. The final figuring
was done by artificial star testing by ".. a glint of sunlight off of a
raven's eye..." at some distance I don't recall.  At the time with the local
ATMs that phrase was the subject of much conversation.  

Some thought he was just full of ... well... they thought he was less than
honest.

I thought he was being a good story teller. And to me at least the fact that
we were all discussing it proved the point. Sometimes a bit of a fib can
communicate a truth better than sticking strictly to the facts.

It was a memorable statement.  You could tell who did or did not read Sky
and Tel. If they asked what we were talking about they must have subscribed
to an alternative magazine.

Well anyway what I thought Dobson was communicating was that telescope
making is not as hard as some people think. And I kind of got a message
something like ..." a lousy mirror in a telescope will show much more than a
mirror on a pitch lap that will never see starlight until it is perfect.

If it were fairly easy to make a mirror to 1/100 wave and 1/200 wave was
possible with much effort and skill, I think there would still be much
discussion of whether one could tell the difference. And some poor souls
would be slaving trying for 1/300 so as not to miss seeing anything.
Therefore they would miss everything.

Jerry 


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